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African experience in the improvement of post-harvest techniques

Table of contents

Based on the workshop help in ACCRA, Ghana 4 - 8 July 1994
Agricultural engineering service, AGSE
Agricultural support systems division

Food and agricultural organization of the United Nations
Rome, Italy


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Chapter 1: Traditional post-harvest systems and their evolution

1.1 Evolution of the environment

1.1.1 Modification of ecological conditions
1.1.2 Technological change
1.1.3 Socio-economic changes

1.2 Improvement of post-harvest techniques

1.2.1 History of improvements to post-harvest operations
1.2.2 The human dimension in the development of post-harvest systems

Chapter 2: Conservation of roots and tubers

2.1 Introduction
2.2 Cassava

2.2.1 Storage of cassava
2.2.2 Processing cassava

2.3 Yams

2.3.1 Storage of yams
2.3.2 Improved storage for yams in Nigeria
2.3.3 Improved yam storage in Benin

2.4 The potato

Chapter 3: Techniques for threshing, shelling and parboiling grain

3.1 The rice harvest

3.1.1 Observations on the traditional method
3.1.2 Introduction of the asian sickle

3.2 Rice threshing

3.2.1 The threshing table
3.2.2 Motorized threshers
3.2.3 The votex thresher

3.3 Parboiling rice

3.3.1 Phases and advantages of parboiling
3.3.2 Experience of rice farmers in the north west of Cameroon

3.4 Improvement of methods of maize shelling

Chapter 4: Grain drying

4.1 Rice drying
4.2 Maize drying

4.2.1 Drying by air convection with supplemental heat
4.2.2 Drying by air convection without supplemental heat
4.2.3 Improved structures
4.2.4 Comparison between traditional and improved structures

Chapter 5: Grain storage

5.1 Traditional storage techniques

5.1.1 Granaries of plant material
5.1.2 Clay granaries
5.1.3 Preparation of granaries
5.1.4 Treatment of grain before storage

5.2 Improved storage techniques

5.2.1 Improvement to maize granaries in the south of Togo
5.2.2 Improvement of storage in the south of Benin

5.3 Silos

5.3.1 The spread of metallic silos in Swaziland
5.3.2 The underground silos in Morocco
5.3.3 Silos of clay reinforced with straw

5.4 Cereal banks

Chapter 6: Post-harvest losses

6.1 Waste and loss

6.1.1 Insects
6.1.2 Moulds
6.1.3 Rodents
6.1.4 Theft and fire

6.2 Techniques for control or preservation

6.2.1 Activities in preparation for storage
6.2.2 Varietal selection
6.2.3 Pesticides
6.2.4 Control of mycotoxins

6.3 Alternative techniques

6.3.1 Local insecticides
6.3.2 Growth regulators
6.3.3 Biological control
6.3.4 Perspectives

Chapter 7: Grain processing

7.1 Hulling and milling local grain

7.1.1 Sorghum and Millet
7.1.2 Description of the technique
7.1.3 The Engleberg-type huller
7.1.4 Abrasive hullers

7.2 Case study on rice hulling in Mali

7.2.1 Introduction of technology
7.2.2 Evaluation of results

7.3 Case study on sorghum porridge

Chapter 8: Grain Quality

8.1 Texture

8.1.1 Maize
8.1.2 Sorghum

8.2 Other characteristics of grain

8.2.1 Shape and size of grain
8.2.2 Thickness of the pericarp
8.2.3 Presence of tannins

8.3 Cleanliness of grain
8.4 The cooking quality of milled products

8.4.1 The colour
8.4.2 The granularity
8.4.3 The texture